Extract from ABC News
Glaciers in the Swiss Alps are on track to record their highest loss of mass in at least 60 years, new data shows.
This follows temperatures peaking at nearly 30 degrees Celsius in the mountain village of Zermatt during an early summer heatwave.
Data from Glacier Monitoring Switzerland and the Universite libre de Bruxelles shows the Morteratsch glacier in the Swiss Alps is shedding about 5 centimetres a day.
The glacier — which is largest by area in the Bernina Range of the Bündner Alps — is in a worse state than it would normally be at the end of summer, according to the data.
Nearby, the Silvretta Glacier has lost about 1 metre more than it had at the same point of summer in 1947, which was the worst year since records started in 1915.
Swiss glaciologist Andreas Linsbauer visits the Morteratsch glacier for the end of the summer melt season every September.
This year he has arrived at the 15-square-kilometre amphitheatre of ice two months early to do emergency maintenance work.
"It's really obvious that this is an extreme season," Mr Linsbauer said.
He uses poles to measure how much the glacier has shrunk by looking at the difference between how much snow fell in winter and how much ice melted in the summer.
During this year's heatwave, the elevation at which water froze was measured at a record high of 5,184 metres.
A normal summer level is between 3,000 to 3,500 metres.
Glaciers will disappear regardless of climate action, UN says
Glaciers in the European Alps are especially vulnerable to climate change because they are smaller than others and have relatively little ice cover.
Temperatures in the alps are warming at around two times as fast as the global average, at about 0.3C per decade.
If greenhouse gas emissions continue to rise, the glaciers in the alps are expected to lose more than 80 per cent of their current mass by 2100.
According to a 2019 report by the United Nations Intergovernmental Panel on Climate Change (IPCC), many glaciers will disappear, regardless of whatever emissions action is taken.
This is due to global warming baked in by past emissions.
The Morteratsch glacier is already different to what is shown on the region's tourist maps.
Its long tongue once reached deep into the valley below but has now shrunk back by nearly 3km.
The depth of the snow and ice pack has thinned by up to 200m.
A parallel glacier called Pers flowed into Morteratsch until 2017, but it has now receded so much that an expanding strip of grit lies between them.
Matthias Huss — who leads Glacier Monitoring Switzerland — said the glaciers may vanish sooner than expected if the weather experienced this year was repeated.
"We are seeing model results expected a few decades in the future are happening now," he said.
"I did not expect to see such an extreme year so early in the century."
Switzerland losing its 'national heritage'
Vanishing glaciers are endangering lives and livelihoods.
On July 3, the collapse of a glacier on the Marmolada in Italy killed 11 people.
Days later, a collapsing glacier in Kyrgyzstan in Central Asia triggered a massive avalanche, which sent ice and rocks hurdling toward passing tourists.
Above the Swiss village of Saas Fee, a path leading to a mountain hut once passed through a summer snowfield on top of the Chessjen Glacier.
It is now too dangerous due to the risk of falling rocks that were once held together by hard-frozen ice.
Nearby, the rumble of stones tumbling from the mountain can be heard.
Swiss residents worry that the glacier losses will hurt their economy.
The Aletsch Glacier is a UNESCO World Heritage Site and Swiss glaciers feature in many of the country's fairy tales.
At ski resorts that rely on glaciers, ice has been covered with white sheets to reflect sunlight and reduce melting.
Hiker Bernardin Chavaillaz said losing the glaciers "means losing our national heritage, our identity".
'Extensive loss' expected by end of summer
Glaciologists in Austria, France and Italy said their countries were also on track for record losses.
"The glaciers are snow-free up to the summits," Austrian Academy of Sciences glaciologist Andrea Fischer said.
Seasonal snowfall replenishes the ice lost during summer. It is also key for protecting glaciers from further melt by providing a white cover that reflects sunlight back out to atmosphere better than darker ice sullied by dust or pollution can.
The Grand Etret glacier in northwest Italy had accumulated 1.3m of snow during the past winter, which is 2m less than the annual average between 2000 and 2020.
This year's Alpine ice losses, registered even before the biggest melt month of August, surprised scientists to some extent, as many of the glaciers had already lost their lower-lying snouts.
"You can easily imagine the final results after summer will be … extensive loss of glacier coverage in the Italian Alps," Italian glaciological committee vice president Marco Giardino said.
Temperatures of 48C hamper Himalayan glaciers
Scientists believe Himalayan glaciers are also on track for a record ice loss this year.
When the summer monsoon season arrived in the Kashmir region, many glaciers had already shrunk drastically.
A heatwave between March and May saw temperatures reach about 48C in northern India, which caused snowlines retreat high up the mountain.
Indian Institute of Technology glaciologist Mohd Farooq Azam said an early June expedition in India's Himachal Pradesh found that the Chhota Shigri Glacier had lost much of its snow cover.
"The highest temperature in over a century in March through May clearly had its impacts," he said.
Reuters
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